Outcomes of Inferior Vena Cava Filter Placement during Pharmacomechanical Thrombectomy for Iliofemoral Vein Thrombosis

Deep vein thrombosis Catheter-directed thrombolysis Pharmacomechanical thrombectomy Inferior vena cava filter Pulmonary embolismObjective The efficacy of routine inferior vena cava (IVC) filter placement during catheterdirected thrombolysis (CDT) or pharmacomechanical thrombectomy (PMT) for iliofemoral deep vein thrombosis (IF-DVT) remains controversial.This study aimed to evaluate whether routine IVC filter placement improves prevention of pulmonary thromboembolism (PTE) or recurrent venous thromboembolism (VTE) in this population.Methods We retrospectively reviewed adults with acute IF-DVT treated with CDT/PMT (March 2021-February 2025) and compared outcomes between a filter group (n=17) and no-filter group (n=21).All patients received six months of oral anticoagulation.The primary outcome was incident PTE within six months.Secondary endpoints included the 6-month composite of recurrent VTE (recurrent deep vein thrombosis and/or PTE), inferior vena cava thrombosis, and target-limb stent occlusion.Results Baseline limb laterality, thrombus extent, and concomitant PTE were similar.Primary outcome: PTE at six months-0/17 (0%) in the filter group vs 1/21 (4.8%) in the nofilter group (p>0.999).Secondary outcomes: recurrent DVT-3/17 (18%) vs 1/21 (4.8%) (p=0.307);IVC thrombosis-1/17 (5.9%) vs 0/21 (0%) (p=0.447);stent occlusion-1/17 (5.9%) vs 2/21 (9.5%) (p>0.999).Event-free survival also did not differ (log-rank p=0.43).Beyond six months, long-term composite events were infrequent with no significant differences. ConclusionIn anticoagulated patients undergoing CDT/PMT for acute IF-DVT, routine prophylactic IVC filter placement did not improve short-or long-term outcomes, including prevention of PTE.These data support a selective, rapid-retrieval strategy for highembolic-risk scenarios.